The management and tracking of personnel, assets, and other objects is required in a wide variety of environments and is often cumbersome, labor intensive, and expensive. Radio receivers and transmitters have been used for many years to identify personnel and objects in such environments. For example, many systems are known for attaching radio tags to items, such as automobiles, so that when automobiles equipped with radio tags enter a certain area, such as a toll booth area, the automobiles are automatically identified and the appropriate tolls are deducted from corresponding accounts, thereby obviating the need for drivers to stop and make payment at toll booths. Innumerable other applications for such radio tag systems have been identified, in areas ranging from inventory control to facility security to sporting event timing.
Radio frequency identification (RFID) systems generally use a fixed position base station capable of reading portable tags attached to personnel, assets, or other objects. Typical base stations include an antenna, a reader, and a computer. If an RFID system covers a large enough area, multiple base stations may be necessary to provide adequate coverage for the large area.
In addition, bandwidth use is high because the base station computer communicates with and processes information from every radio tag within its operational range. The lack of available bandwidth limits multi-read capabilities of the system which allows a base station to interact with more than one radio tag at any particular time.